Blister packs have become common place in the retail sale of consumer goods such as over-the-counter and prescription pharmaceuticals, gum, mints, and other small consumer goods and products. In essence, a blister pack is a two-part container. The first part is a plastic tray that includes several cavities or pockets (herein inclusively referred to as “cells”) into which items can be placed. The second part is a flat seal layer of aluminum foil, plastic, paperboard, or the like that is secured to the tray so as to seal the cells. Items are removed from the cells by breaking the section of the seal layer above the cell. Such sealing not only retains the items in the cavities or pockets, but can also protect the items for contamination, spoiling, tampering, and the like. If there is a hole, tear, or other defect or other discontinuity in the seal layer, the items in the cells can be exposed to the surrounding environment. It will be understood that such exposure can be detrimental to the product, particularly when the product is a pharmaceutical or food product. Systems and methods are desired that can determine the integrity of the seal layer, particularly where the portion of the seal layer is above cells in the blister pack.
Another aspect of the need to monitor if a cell had been opened and the product removed is in compliance monitoring. The activity allow a healthcare professional or other care giver to determine remotely if a medication regime is being followed, for example the correct drugs being taken at the correct time, by patients such as the elderly, as this can be very important in their treatment.
Methods of determining the presence of a discontinuity in a medium are known. One example is SONAR, where a discontinuity is the presence of a vessel or other large object below the surface of a body of water. When a sound wave moves through the water, it will reflect off a vessel back in the direction of origin and can be detected. When the reflective wave is detected, it can be analyzed and concussions can be drawn about the location and other characteristics of the vessel. Another example is non-destructive testing, where features such as cracks or other defects are considered the discontinuities. For a blister pack, the mechanical structure of the pack is modified when the seal layer above a cell is opened, which is considered an discontinuity. Such discontinuity is appropriate when it is intended, for example, when an item is intentionally removed from its cell. However, during shipping or storage, such discontinuities are unwanted and can harm the items in the exposed cells. Determining a discontinuity in the blister pack can result in the appropriate removal of the blister pack form commerce because the blister pack may be non-compliant with safety and other standards.
There are current methods and systems available for determining when a cell in the blister pack has its seal broken. However, such current methods and systems require manual inspection or the use of specialized sealing film to determine when there is a discontinuity in a blister pack. There is a need for improvement to existing methods and systems that provide for the determination of blister pack compliance.